Thermal quantum discord and classical correlations in a two-qubit Ising model under a site-dependent magnetic field

Thermal quantum discord and classical correlations in a two-qubit Ising model under a...
Terzis, Andreas; Androvitsaneas, Petros; Paspalakis, Emmanuel
2011-12-25 00:00:00
We investigate the thermal quantum discord and classical correlations in a two-qubit Ising model interacting with a site-dependent external magnetic field. Systematic study of all correlations is performed for various values of the system’s temperature, and the magnetic field magnitude and direction on each site. Our results reveal interesting findings as regrowth regions of the classical and quantum correlations. Moreover unexpected bahavior as for example increase of the quantum correlations with the increase of the anisotropy of the applied magnetic fields for specific values of the external parameters is reported. By comparing our quantum discord data with the entanglement of formation, we have concluded that the major source of quantum correlations is the entanglement. Overall, we have found that the independent control of each spin site by external fields is a very practical and robust way of achieving significant quantum discord useful in quantum computation and information proccesses.
http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.pngQuantum Information ProcessingSpringer Journalshttp://www.deepdyve.com/lp/springer-journals/thermal-quantum-discord-and-classical-correlations-in-a-two-qubit-1U4HHWYq0l

Thermal quantum discord and classical correlations in a two-qubit Ising model under a site-dependent magnetic field

Abstract

We investigate the thermal quantum discord and classical correlations in a two-qubit Ising model interacting with a site-dependent external magnetic field. Systematic study of all correlations is performed for various values of the system’s temperature, and the magnetic field magnitude and direction on each site. Our results reveal interesting findings as regrowth regions of the classical and quantum correlations. Moreover unexpected bahavior as for example increase of the quantum correlations with the increase of the anisotropy of the applied magnetic fields for specific values of the external parameters is reported. By comparing our quantum discord data with the entanglement of formation, we have concluded that the major source of quantum correlations is the entanglement. Overall, we have found that the independent control of each spin site by external fields is a very practical and robust way of achieving significant quantum discord useful in quantum computation and information proccesses.

Journal

Quantum Information Processing
– Springer Journals

Published: Dec 25, 2011

Recommended Articles

Loading...

References

A measure of the quantumness of correlations

Ollivier, H.; Zurek, W.H.

Classical, quantum and total correlations

Henderson, L.; Vedral, V.

Quantum discord and the power of one qubit

Datta, A.; Shaji, A.; Caves, C.M.

Experimental quantum computing without entanglement

Lanyon, B.P.; Barbieri, M.; Almeida, M.P.; White, A.G.

Quantum discord for two-qubit X states

Ali, M.; Rau, A.R.P.; Alber, G.

Quantum discord for two-qubit systems

Luo, S.

Quantum correlations in a clusterlike system

Chen, Y.X.; Li, S.W.; Yin, Z.

Thermal quantum and classical correlations in a two-qubit XX model in a nonuniform external magnetic field

Hassan, A.; Lari, B.; Joag, P.

Amplification of quantum discord between two uncoupled qubits in a common environment by phase decoherence

Yuan, J.B.; Kuang, L.M.; Liao, J.Q.

Decoherence of quantum discord in an asymmetric-anisotropy spin system

Hao, X.; Ma, C.L.; Sha, J.Q.

Quantum discord induced by a spin chain with quantum phase transition

Sun, Z.; Lu, X.M.; Song, L.J.

Optimal measurements to access classical correlations of two-qubit states

Lu, X.-M.; Ma, J.; Xi, Z.; Wang, X.

Maximally discordant mixed states of two qubits

Galve, F.; Giorgi, G.L.; Zambrini, R.

Quantum discord for general two-qubit states: analytical progress

Girolami, D.; Adesso, G.

Entanglement and the power of one qubit

Datta, A.; Flammia, S.T.; Caves, C.M.

Experimental quantum computing without entanglement

Lanyon, B.P.; Barbieri, M.; Almeida, M.P.; White, A.G.

Robustness of quantum discord to sudden death

Werlang, T.; Souza, S.; Fanchini, F.F.; Villas Boas, C.J.

Natural thermal and magnetic entanglement in the 1D Heisenberg model

Arnesen, M.C.; Bose, S.; Vedral, V.

Entanglement in the quantum Heisenberg XY model

Wang, X.G.

Thermal concurrence mixing in a one-dimensional Ising model

Gunlycke, D.; Kendon, V.M.; Vedral, V.; Bose, S.

Enhanced thermal entanglement in an anisotropic Heisenberg XYZ chain

Zhou, L.; Song, H.S.; Guo, Y.Q.; Li, C.

Thermal entanglement in the two-qubit Heisenberg XY model under a nonuniform external magnetic field